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To characterize the correlation, agreement and concordance of cardiac output (CO) measured with transthoracic ultrasound and the correlation and concordance of aortic blood flow (ABF) minute distance (MD) measured by transesophageal Doppler with CO measured by pulmonary artery thermodilution (PATD) in cats. Experimental study. A group of six healthy male neutered cats, aged 2–8 years and weighing 5.3 ± 0.3 kg. Cats were anesthetized with isoflurane in oxygen. CO was measured by PATD (CO PATD) and transthoracic echocardiography (CO ECHO). ABF MD was measured using an esophageal Doppler flow probe aligned with descending ABF. All measurements were made under three conditions: dexmedetomidine (20 μg kg–1) intravenously; atipamezole (200 μg kg–1) intramuscularly and atropine (20 μg kg–1) intravenously as needed to achieve a minimum heart rate of 140 beats minute–1; and dopamine (20 μg kg–1 minute–1) intravenously in that order. Correlation between CO PATD and CO ECHO , and CO PATD and Doppler MD was evaluated using repeated measures correlation. Agreement between CO PATD and CO ECHO was evaluated using Bland–Altman method. Differences between consecutive pairs of CO measurements were calculated for concordance analysis. Correlation between CO PATD and CO ECHO and between CO PATD and MD was significant (p < 0.001), with correlation coefficients greater than 0.92. A bias of > 27% and upper limits of agreement of 66% were found between CO PATD and CO ECHO. Concordance rate with CO PATD was 76–80% for CO ECHO and 72% for MD. Echocardiographic methods for the measurement of CO showed poor agreement and concordance with PATD. MD showed poor concordance with PATD. As such, these methods cannot be used as an alternative to PATD nor can they appropriately track changes in CO in anesthetized cats. [ABSTRACT FROM AUTHOR]

• Biopsy for asymptomatic postmenopausal women if endometrial thickness is ≥8 mm. • For 4-8 mm, consider biopsy after evaluating risk factors and blood flow signals. To determine the cutoff value for endometrial thickness (ET) that prompts a biopsy in asymptomatic postmenopausal women with an incidental finding of thickened endometrium, and to develop a risk prediction model. This is a retrospective cohort analysis of the clinical records of the Hysteroscopic Center of Fu Xing Hospital, Capital Medical University, Beijing, China. We collected asymptomatic postmenopausal women who presented with an ET of ≥4 mm (double-layer) as an incidental finding. We stratified the participants into non-malignant and malignant groups based on pathology results and assessed differences between the two groups. A receiver operating characteristic curve (ROC) was used to identify the cutoff value of ET for predicting endometrial malignancy. Logistic regression models were also constructed to predict the risk of malignancy. A total of 581 consecutive eligible cases were included. The optimal cutoff value for ET was 8 mm, with a maximum area under the curve (AUC) of 0.755 (95 % CI: 0.645–0.865). In addition to ET, the regression model incorporated diabetes, blood flow signal, BMI, and hypertension to predict the risk of malignancy. A ROC curve constructed for the model yielded an AUC of 0.834 (95 % CI: 0.744–0.924). It is reasonable to offer hysteroscopy and visually-directed endometrial biopsy for asymptomatic postmenopausal women when ET is 8 mm or above. For those with an ET between 4 and 8 mm, further decision to perform biopsy should be determined on an individual basis, considering risk factors and blood flow signals of the endometrium. [ABSTRACT FROM AUTHOR]

Infrared thermography technology is a noninvasiveness and real-time imaging method, it has attracted enormous attentions for blood flow imaging. However, the implementation of infrared thermography technology is still limited by the poor imaging quality caused by the low temperature discrimination between the target blood vessel and background. Herein, we reported a flexible and low-cost MXene based photothermal microheater for enhancing the infrared imaging of blood flow. In the experiment, MXene films with specific thickness was prepared by vacuum filtering different concentrations of MXene colloidal solutions. Thereafter, the microheaters were fabricated by assembling the MXene films on the PU tape/PDMS substrate, and then sealed with another layer of pure PDMS film on the top of MXene film. The photothermal performance of the microheaters were evaluated by using an 808-nm laser as the exciting source. Experimental results show that the optimal microheater (MXene content: 17.5 ​mg) can reach a safe temperature of 41.5 ​°C with 43.9 ​s under the light irradiation of 100 ​mW·cm−2. Moreover, it can be stabilized at the equilibrium temperate for over 25 ​min. Finally, the above optimal microheater was used to accurately heat the simulated blood vessel. It shows that temperature difference of 3.3 ​°C can be induced between the heated blood vessel and environment. As a result, it significantly enhances the quality of the infrared imaging of the blood flow in the simulated vascular network. [Display omitted] • A MXene based flexible microheater is prepared. • The microheater owns excellent photothermal performance under the NIR-laser irradiation. • The microheater is used to accurately heat the simulated vessel. • High-quality the infrared imaging of the blood flow in the simulated vesselwas obtained by using the microheater. [ABSTRACT FROM AUTHOR]

Surgical treatment of large or giant thrombosed anterior cerebral artery (ACA) aneurysms often involves revascularization. Herein, we describe a unique and effective bypass technique to treat partially thrombosed giant distal ACA aneurysms in extremely narrow surgical corridors. A 68-year-old man underwent aneurysm trapping and ACA revascularization for a partially thrombosed giant ACA aneurysm in a surgical corridor that was narrow due to anatomic factors. By combining a side-to-side anastomosis and an end-to-side anastomosis at a single anastomotic site, we successfully redirected blood flow from the left pericallosal artery to the right pericallosal and callosomarginal arteries. Postoperatively, cerebral angiography showed that the blood flow in the aneurysm had disappeared, and the bypass remained open. The patient's functional disability gradually improved, and he reported consistently positive outcomes at the 6-month postoperative follow-up examination. This revascularization technique may represent an effective novel treatment option, particularly when multiple revascularization procedures are required within a narrow surgical field. [ABSTRACT FROM AUTHOR]

Cervical spinal cord injury usually results in cardiorespiratory dysfunctions due to interruptions of the bulbospinal pathways innervating the cervical phrenic motoneurons and thoracic sympathetic preganglionic neurons. The present study aimed to evaluate the therapeutic effects of adrenergic agents on systemic and spinal hemodynamics during acute cervical spinal cord injury. In vivo animal study. The cardiorespiratory function and spinal cord blood flow and oxygenation level were monitored in response to cervical spinal cord contusion and intravenous infusion of three types of adrenergic agents (phenylephrine, dobutamine, and norepinephrine). Cervical spinal cord contusion resulted in immediate reduction of respiratory airflow, arterial blood pressure, and spinal cord blood flow. The arterial blood pressure and spinal cord blood flow remained lower than the preinjury value in contused animals infused with saline at 60 min postinjury. Infusion of phenylephrine (500, 1000, and 2000 μg/kg) and norepinephrine (125, 250, and 500 μg/kg) significantly increased the arterial blood pressure, while only norepinephrine augmented the spinal cord blood flow. Conversely, dobutamine (1000 and 2000 μg/kg) reduced both arterial blood pressure and spinal cord blood flow. Notably, administration of adrenergic agents tended to increase spinal cord hemorrhage in contused animals. Infusion of norepinephrine can effectively maintain the blood pressure and improve spinal cord blood flow during acute spinal cord injury. Norepinephrine may be a superior medicine for hemodynamic management; however, the potential hemorrhage should be considered when utilizing the vasopressor to regulate systemic and spinal hemodynamics at the acute injured stage. [ABSTRACT FROM AUTHOR]

To investigate the relationship between left atrial appendage (LAA) morphology, quantified based on fractal dimension (FD), and LAA hemodynamic parameters in patients with atrial fibrillation (AF), in an effort to reveal the effect of LAA shape on blood flow. 225 patients with AF who underwent cardiac computed tomography angiography (CTA) and transesophageal echocardiography (TEE) were enrolled. LAA morphology was quantified based on FD on cardiac CTA images, and LAA hemodynamic parameters, including injection fraction (EF), filling peak flow velocity (FV), maximum speed of emptying (PEV), and wall motion velocity (WMV), were assessed using TEE. We divided the patients with AF into two groups based on a mean LAA FD of 1.32: the low FD group (n=124) and the high FD group (n=101). Compared to the low FD group, there were more patients with LAA circulatory stasis/thrombus (P =0.008) in the high FD group, as well as lower LAA FV (P =0.004), LAA PEV (P =0.007), and LAA WMV (P =0.007). LAA FD was an independent and significant determinant of LAA EF (β = -11.755, P =0.001), LAA FV (β = -17.364, P =0.004), LAA PEV (β = -18.743, P <0.001), and LAA WMV (β = -7.740, P =0.001) in multiple linear regression analysis. LAA FD is an essential determinant of LAA hemodynamic parameters, suggesting that the relatively complex morphology of the LAA may influence its hemodynamics, which can correlate with embolic events. • To investigate the relationship between LAA FD and LAA hemodynamic parameters. • LAA FD was negatively associated with LAA EF, LAA FV, LAA PEV, and LAA WMV. • LAA FD was an independent determinant of LAA EF, LAA FV, LAA PEV, and LAA WMV. [ABSTRACT FROM AUTHOR]

We devised a method that combines the 3D-Dixon-gradientecho (GRE) method with an improved motion-sensitized driven-equilibrium (iMSDE) to suppress blood flow signals. The purpose of this study was to evaluate the effectiveness of the new method we developed plaque imaging method (3D-Dixon-GRE with the iMSDE method). Retrospective cohort. Thirty-nine patients who underwent cervical plaque imaging. FIELD STRENGTH/SEQUENCE:3.0 T/3D-GRE. Signal intensities of the common carotid artery, aorta, plaque, muscle, and subcutaneous fat were measured through the VISTA and the 3D-Dixon-GRE with iMSDE methods, and each contrast was calculated. Used the Mann Whitney U test. P -values below 0.05 were considered statistically significant. Plaque and muscle contrast estimated through the VISTA method and 3D-Dixon-GRE with iMSDE method was 1.60 ± 0.96 and 2.04 ± 1.06, respectively, (P < 0.05). The contrast between the flow (common carotid artery and Aorta) and muscle according to the VISTA method and 3D-Dixon-GRE with iMSDE method was 0.24 ± 0.11 and 0.40 ± 0.12, respectively (P < 0.001). Finally, the mean contrast for subcutaneous fat and muscle at six locations was 3.05 ± 1.25 and 0.81 ± 0.23 for the VISTA method and 3D-Dixon-GRE with the iMSDE method, respectively (P < 0.001). Compared to the conventional method (VISTA), the 3D-Dixon-GRE with iMSDE method is preferable in relation to the fat suppression effect, but it is disadvantageous regarding blood flow signal suppression. Therefore, the 3D-Dixon-GRE with the iMSDE method could be considered useful for plaque imaging. [Display omitted] [ABSTRACT FROM AUTHOR]

• MVFI can display the real-time perfusion status of fetal microvessels, including blood flow velocity, volume, and other related parameters. This technology is a non-invasive method that can be used to evaluate the blood flow situation in the fetal cranial region. • Growth restricted fetuses have lower biparietal diameter, head circumference, abdominal circumference, and femur length than normal fetuses, and their microvascular index and peak systolic velocity of internal arteries are also lower than normal fetuses. • The larger the microvascular index and peak systolic velocity of the internal artery, the more severe the fetal growth restriction. The study conducted retrospective analysis design, aiming to explore the use of Microvascular Imaging Technique (MVFI) to assess fetal cerebral microcirculation and analyze the relationship between Microvascular Index (MVI) and fetal growth and development. 100 pregnant women who met the criteria for fetal growth restriction (FGR) provided in the Expert Consensus on Fetal Growth Restriction (2019 Edition) and underwent routine prenatal examinations at the Obstetrics and Gynecology Department of Peking University Third Hospital from January 2021 to June 2023 were selected as the study subjects. A normal fetus with a fetal weight less than 10 % can be classified as FGR, Pregnant women with fetal umbilical artery (UA) systolic and diastolic (S/D) values ≥3 were included in the observation group, while 200 pregnant women with normal fetuses were selected as the control group during the same period. The fetuses' change in both groups were measured using color Doppler ultrasound, including bi-parietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL). The cerebral microcirculation of the fetuses in both groups was evaluated using MVFI, and the MVI values were compared. The clinical characteristics of FGR fetuses with umbilical artery S/D ratio ≥ 3 were summarized, and the correlation between fetal cerebral microvascular status and fetal growth and development was analyzed using Pearson correlation analysis. The outcomes told that the BPD, HC, AC, and FL values of the fetuses in the control group were lower the other's value (P < 0.05), and the MVI and peak systolic velocity of the middle cerebral artery (MCA-PSV) values were also lower in the control group (P < 0.05). Pearson correlation analysis revealed a positive correlation between fetal growth and development and MVI and MCA-PSV values in FGR fetuses. In conclusion, MVFI can monitor and quantitatively analyze fetal intracranial microcirculation, visualize slow blood flow in microvascular structures, and this study provides preliminary evidence of the close relationship between fetal cerebral microcirculation and intrauterine growth and development. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the feasibility of performing multiple testicular biopsies in rams using Tru-cut® needles, assessing histological structure, gene expression, and potential complications such as effects on semen quality, testicular blood flow, and ultrasonographic echotexture. In Exp. 1, six mature rams underwent testicular biopsies at intervals (0, 3, 6, 12, 24, and 48 h) using a 16 G Tru-cut® needle, with alternating testes for each collection. Benzathine benzylpenicillin and flunixin meglumine were administered for infection and inflammation control. Local anesthesia and post-biopsy care included lidocaine, digital pressure, and ice application. Testicular samples were analyzed for gene expression related to inflammation, oxidative stress, and steroidogenesis. Semen quality was assessed pre-biopsy and 28 days post-biopsy. Ultrasonographic evaluations of the scrotum and testes were conducted before biopsies and on days 5, 9, 13, 17, and 21 post-biopsies. In Exp. 2, a second group of six mature rams underwent biopsies using 14 G needles, with two samples taken from each testis. Samples were histologically examined for structural preservation. Scrotal skin temperature was measured using infrared thermography, and testicular blood flow was assessed via color Doppler ultrasonography, with measurements taken before and on days 1, 2, 4, 6, 8, 10, 25, 50, 75, and 100 post-biopsies. Semen collection followed the same schedule as in Exp. 1. In Exp. 3, biopsies were performed on different testicular regions (upper, middle, lower) using 12 G, 14 G, and 16 G needles to compare structural preservation. Samples were histologically analyzed. No clinical signs of injury, inflammation, or fluid accumulation were observed. Scrotal pain, increased temperature, swelling, and bleeding were absent, and behavioral signs indicative of pain were not detected. Gene expression remained unchanged, and no significant alterations in seminal characteristics or testicular echogenicity were observed. A slight increase in resistivity and pulsatility indices was noted in Exp. 2. Biopsies with 14 G and 16 G needles resulted in structural disruptions, while 12 G needles better preserved testicular parenchyma. Multiple testicular biopsies using Tru-cut® needles did not cause significant morphological changes, alter transcriptional profiles, or affect semen or ultrasonographic characteristics, demonstrating that this method is viable for monitoring acute molecular changes in the testes. • Tru-cut testicular biopsies in rams allowed effective assessment of histological and transcriptional profiles with minimal adverse effects. • Multiple testicular biopsies do not significantly alter scrotal or testicular morphology or function. • This approach did not affect seminal, or testes ultrasonographic or the blood flow testicular characteristics. • This approach aids in developing animal models to study testicular diseases, advancing reproductive health research. [ABSTRACT FROM AUTHOR]

Mechanotransduction is an evolutionary conserved and essential physiological process enabling cells to sense and convert mechanical stimuli into intracellular electrochemical events. Transient receptor potential (TRP) channels have been implicated in numerous mechanotransduction processes, including cancer cell migration, bone mineralization, and sensing blood flow. However, limited evidence supports TRP channels acting as primary mechanotransducers – those that directly sense and convert the external stimuli into an intracellular signal. Most evidence is congruent with TRP channels instead acting as molecular amplifiers responding downstream of the activation of a primary mechanotransducer (such as PIEZO1 or PIEZO2), forming mechanosensory modules. Here, we discuss the evidence supporting TRP channels as primary mechanotransducers and alternative models whereby TRP channels together with primary mechanotransducers could contribute to mechanosignalling. Transient receptor potential (TRP) channels are implicated in a wide array of mechanotransduction processes. However, a question remains whether TRP channels directly sense mechanical force, thus acting as primary mechanotransducers. We use several recent examples to demonstrate the difficulty in definitively ascribing mechanosensitivity to TRP channel subfamilies. Ultimately, despite being implicated in an ever-growing list of mechanosignalling events in most cases limited robust or reproducible evidence supports the contention that TRP channels act as primary transducers of mechanical forces. They either (i) possess unique and as yet unspecified structural or local requirements for mechanosensitivity; or (ii) act as mechanoamplifiers responding downstream of the activation of a primary mechanotransducer that could include Ca2+-permeable mechanosensitive (MS) channels or other potentially unidentified mechanosensors. [ABSTRACT FROM AUTHOR]

The accurate measurement of the wall shear rate (WSR) plays a crucial role in the early diagnosis of cardiovascular disease progression and acute events such as aneurysms and atherosclerotic plaque ruptures. To address this need, the speckle decorrelation (SDC) technique has been used to measure WSR based on the 2-D out-of-plane blood flow speed. This technique is particularly advantageous because it enables the use of a 1-D array transducer to measure WSR over the entire luminal area. This study aims to develop a region-based singular value decomposition (SVD) filtering technique that selectively suppresses clutter noise in the vascular region to measure WSR using SDC. Ultrasound simulations, in-vitro flow experiments, and an in-vivo human study were conducted to evaluate the feasibility of this method's clinical application. The results demonstrated that WSR can be effectively measured across entire vascular walls using a conventional 1-D array transducer along with the proposed methodology. This study successfully demonstrates a noninvasive and accurate SDC-based method for measuring vital vascular WSR. This approach holds significant promise for assessing vascular WSR in both healthy individuals and high-risk cardiovascular disease patients. [ABSTRACT FROM AUTHOR]

• DMV contains cardiac and pulmonary parasympathetic motoneurons controlling ventricular function and airways secretion. • DMV pulmonary motoneurons are more depolarized and excitable than cardiac. • DMV pulmonary motoneurons have both lower magnitude of A-type K+ currents and level of Kv4.2 expression than cardiac. • DMV pulmonary motoneurons receive greater excitatory synaptic inputs and have highly dendritic complexity than cardiac. The dorsal motor nucleus of the vagus (DMV) contains parasympathetic motoneurons that project to the heart and lungs. These motoneurons control ventricular excitability/contractility and airways secretions/blood flow, respectively. However, their electrophysiological properties, morphology and synaptic input activity remain unknown. One important ionic current described in DMV motoneurons controlling their electrophysiological behaviour is the A-type mediated by voltage-dependent K+ (Kv) channels. Thus, we compared the electrophysiological properties, synaptic activity, morphology, A-type current density, and single cell expression of Kv subunits, that contribute to macroscopic A-type currents, between DMV motoneurons projecting to either the heart or lungs of adult male rats. Using retrograde labelling, we visualized distinct DMV motoneurons projecting to the heart or lungs in acutely prepared medullary slices. Subsequently, whole cell recordings, morphological reconstruction and single motoneuron qRT-PCR studies were performed. DMV pulmonary motoneurons were more depolarized, electrically excitable, presented higher membrane resistance, broader action potentials and received greater excitatory synaptic inputs compared to cardiac DMV motoneurons. These differences were in part due to highly branched dendritic complexity and lower magnitude of A-type K+ currents. By evaluating expression of channels that mediate A-type currents from single motoneurons, we demonstrated a lower level of Kv4.2 in pulmonary versus cardiac motoneurons, whereas Kv4.3 and Kv1.4 levels were similar. Thus, with the distinct electrical, morphological, and molecular properties of DMV cardiac and pulmonary motoneurons, we surmise that these cells offer a new vista of opportunities for genetic manipulation providing improvement of parasympathetic function in cardiorespiratory diseases such heart failure and asthma. [ABSTRACT FROM AUTHOR]

• Acute ischemic stroke thrombi have a complex and heterogeneous composition. • The composition of the thrombus affects the response to thrombolysis. • Thrombus composition determines thrombectomy success parameters. Ischemic stroke is caused by a thrombus blocking one or multiple arteries in the brain, resulting in irreversible damage in the associated brain tissue. The aim of therapy is to restore the blood flow as fast as possible. Two recanalization strategies are currently available: pharmacological thrombolysis using recombinant tissue plasminogen activator (rt-PA) and mechanical removal of the thrombus. Despite recent advancements, achieving efficient recanalization remains a challenge. The precise causes of therapy failure are not fully understood but thrombus composition is likely a key factor in successful recanalization. This review explores acute ischemic stroke thrombus composition, its recently identified components, and how it affects stroke treatment. It also discusses how new insights could enhance current recanalization strategies for ischemic stroke patients. [ABSTRACT FROM AUTHOR]

The study on arterial stenosis has gained rapid interest among researchers in the last decade because of its chronic consequences. Several researchers have tried to investigate stenosis and plaque progression in the carotid artery with different simulation models. In this study, a realistic 3-D geometry of the carotid artery has been used to analyze the effect of varying degrees of stenosis present at different locations of the carotid artery on various hemodynamic parameters. An extensive range of stenosis degrees, starting from a healthy artery(0 %stenosis) to 10%, 30%, 50%, 75%, and 90% stenosis, have been studied. These degrees of stenosis were planted at different locations of the artery grown simultaneously. The whole study was done under the realm of Fluid–Structure Interaction multiphysics. The change in velocity profiles at the areas of stenosis has been found along with the wall shear stress and arterial displacement. The magnitude of velocity and wall shear stress in the case of multiple stenosis locations has been found to be dependent on each other. The presence or absence of one stenosis affects the other, and given the regular and irregular patterns of the velocity profile, wall shear stress, and displacement, their inclusion in blood flow simulation studies having multiple stenoses should be considered. [ABSTRACT FROM AUTHOR]

A detailed study of the effect of coarctation on the blood flow of the thoracic aorta was carried out by modeling the interaction between blood and the aortic wall. Fluid-structure interaction (FSI) simulations were performed on the thoracic aorta geometries of healthy and diseased patients obtained from medical images. The pulsating flow of non-Newtonian blood was set by the boundary condition for the velocity in the form of a periodic physiological wave depending on time. As a result, the parameters of blood flow and vessel deformation were evaluated. It is shown that the velocity value at the site of aortic narrowing increases and falls after the narrowing. In addition, it can be noted that the value of pressure in the healthy aorta was higher than in the aorta with CoA, but at the same time, the pressure in the CoA model increased after the coarctation zone. It was noted that the shear stresses for the two models showed little difference and WSS was overestimated in the diseased aorta. As can be seen from the obtained data, using numerical simulation, important characteristics were determined to assess the influence of the fluid-structure interaction during blood flow in the flexible stenotic thoracic aorta. [ABSTRACT FROM AUTHOR]

• There is a question whether depressed mood is really associated with vascular dysfunctions due to their commonness in the elderly. • We showed correlations between depressed mood severity and vascular properties in patients suffering from COVID-19 3–6 months earlier. • The results seem to confirm the vascular depression hypothesis and indicate non-neurological factors impacting some mental properties. Vascular depression hypothesis (VDH) bases on co-occurrence of vascular and mental dysfunctions in advanced age; however, there may be still a controversy about whether there is some direct association between vascular and mental properties or the co-occurrence is only a statistical artifact caused by commonness of these dysfunctions in the elderly. COVID-19 gave opportunity to test VDH under conditions different from aging. 25 patients were examined 3–6 month after SARS-CoV-2 infection. Subjective worsening of mental functions, presumably caused by the disease, was quantified with three psychometric tests. Blood flow waveforms were obtained for the left brachial and common carotid arteries. The waveform shape changes continuously with age; therefore, an individual shape can be characterized by the index WA being the calendar age (CA) of the average healthy rested subject having the most similar shape (consequently, in healthy rested subjects WA-CA = 0, in average). The mathematical functional analysis was used to calculate WA. Brachial WA-CA = 13 yrs, in average (p < 0.00005; Cohen's d = 0.99), and was correlated with tests scores (r = 0.55, 0.65, 0.46). Mean carotid WA-CA were smaller (7.2 and 1.6) but they were also correlated with the scores (right: r = 0.44, 0.55, 0.32; left: r = 0.49, 0.51, 0.38). Scores of two tests were inversely correlated with the systolic (r = -0.54, −0.58) and diastolic (r = -0.46, −0.56) pressures. Since neither vascular nor mental problems are common after COVID-19, these relatively high correlations indicate that vascular and mental properties are not independent, i.e., they support VDH. Note that this not only concerns cerebral vasculature. [ABSTRACT FROM AUTHOR]

• The findings are consistent in showing greater deoxygenation in the muscles during exercise, reflecting the oxygen (O 2) utilization. • Muscle O 2 availability becomes compromised when an individual reaches the exhaustion point by reducing blood flow and decreasing muscle O 2 extraction. • Cerebral tissue experiences an increase in O 2 delivery with increased exercise intensity, suggesting a greater engagement of the brain areas to sustain the exercise. • At the exhaustion point, cerebral oxygenation reaches a plateau or decline, potentially resulting in motor failure during exercise. Near-infrared spectroscopy (NIRS) technology has allowed for the measurement of cerebral and skeletal muscle oxygenation simultaneously during exercise. Since this technology has been growing and is now successfully used in laboratory and sports settings, this systematic review aimed to synthesize the evidence and enhance an integrative understanding of blood flow adjustments and oxygen (O 2) changes (i.e., the balance between O 2 delivery and O 2 consumption) within the cerebral and muscle systems during exercise. A systematic review was conducted using PubMed, Embase, Scopus, and Web of Science databases to search for relevant studies that simultaneously investigated cerebral and muscle hemodynamic changes using the near-infrared spectroscopy system during exercise. This review considered manuscripts written in English and available before February 9, 2023. Each step of screening involved evaluation by 2 independent authors, with disagreements resolved by a third author. The Joanna Briggs Institute Critical Appraisal Checklist was used to assess the methodological quality of the studies. Twenty studies were included, of which 80% had good methodological quality, and involved 290 young or middle-aged adults. Different types of exercises were used to assess cerebral and muscle hemodynamic changes, such as cycling (n = 11), treadmill (n = 1), knee extension (n = 5), isometric contraction of biceps brachii (n = 3), and duet swim routines (n = 1). The cerebral hemodynamics analysis was focused on the frontal cortex (n = 20), while in the muscle, the analysis involved vastus lateralis (n = 18), gastrocnemius (n = 3), biceps brachii (n = 5), deltoid (n = 1), and intercostal muscle (n = 1). Overall, muscle deoxygenation increases during exercise, reaching a plateau in voluntary exhaustion, while in the brain, oxyhemoglobin concentration increases with exercise intensity, reaching a plateau or declining at the exhaustion point. Muscle and cerebral oxygenation respond differently to exercise, with muscle increasing O 2 utilization and cerebral tissue increasing O 2 delivery during exercise. However, at the exhaustion point, both muscle and cerebral oxygenation become compromised. This is characterized by a reduction in blood flow and a decrease in O 2 extraction in the muscle, while in the brain, oxygenation reaches a plateau or decline, potentially resulting in motor failure during exercise. [Display omitted] [ABSTRACT FROM AUTHOR]

Mucopolysaccharide polysulfate (MPS) is widely used as an active ingredient in topical preparations for the treatment of asteatosis and blood flow disorders. Although topical MPS products can increase cutaneous blood flow (CBF), the underlying mechanism remains unclear. In this study, we aimed to elucidate how MPS increases CBF. We investigated the association of nitric oxide (NO), a powerful mediator associated with increased local blood volume, with the blood flow-accelerating action of MPS in mice. In addition, we verified the effects of MPS on NO production in different skin cell types, such as keratinocytes (KCs), endothelial cells (ECs), and dermal fibroblasts (DFs). We used raster-scanning optoacoustic imaging mesoscopy to observe in vivo changes in the skin blood volume. NO production was determined in each cell using an NO indicator. An enzyme-linked immunoassay was used to measure the phosphorylated nitric oxide synthase (NOS) levels in ECs, DFs, and KCs in the presence or absence of MPS. Topical application of MPS increased the skin blood volume in mice, and this increase was abolished through the addition of NOS inhibitors. MPS promoted the dose-dependent production of NO in various cells, which caused alterations in the phosphorylation state of NOS. Our findings demonstrate that MPS promotes an increase in skin blood volume and NO production in various skin cell types. These results suggest that MPS can potentially accelerate CBF through the NO biosynthesis pathway in different skin cell types. • Topical MPS cream increased local skin blood volume in mice. • NOS inhibitor attenuated MPS-induced increase in local skin blood volume. • MPS enhanced intracellular or extracellular NO production in ECs, DFs, and KCs. • MPS-induced NO production is blocked by cNOS inhibition. • MPS promoted eNOS Ser1177 phosphorylation and nNOS Ser852 dephosphorylation. [ABSTRACT FROM AUTHOR]

Gray-scale sonography in combination with color Doppler imaging is the imaging modality of choice for evaluating scrotal disease because it delivers excellent spatial resolution and assists in the identification and characterization of scrotal masses. Most Intratesticular lesions usually show hypoechoic, are malignant but benign masses has been reported. The differentiation between malignant and benign lesions is important because the treatment is different. Sonography permits differentiation between intratesticular lesions and extra-testicular lesions. In this article, we review the relevant literature and discuss the sonographic and clinical features of different types of intratesticular hypoechoic masses. Familiarity with the sonographic appearances of benign and malignant testicular lesions may allow specific diagnosis. The patient is scanned in the supine position with a folded towel positioned between the patient's legs to support the scrotum. The penis is positioned over the patient's suprapubic region and draped with a second towel. The scanning is performed with a 5- to 12-MHz linear array transducer. Serial transverse and sagittal images of each testis and epididymis are obtained in addition to at least 1 image showing both testicles for direct comparison of testicular echogenicity, echo texture, and scrotal thickness. Color Doppler sonography is used to assess and document blood flow in the testis. The power level, threshold persistence, and wall filter should adjusted to maximize the detection of blood flow through the field of view. Intratesticular cysts including cysts of the tunica albuginea, tubular ectasia of the rete testis, and testicular cysts. Testicular cysts have the typical appearance of other cysts, well defined anechoic structures with increased through transmission. Tubular ectasia of the rete testis showed as hypoechoic branching cystic configurations in the mediastinum testis. These findings may be associated with a spermatocele in the same size. [ABSTRACT FROM AUTHOR]

Blood flow to the brain is a critical physiological function and is useful to monitor in critical care settings. Despite that, a surrogate is most likely measured instead of actual blood flow. Such surrogates include velocity measurements in the carotid artery and systemic blood pressure, even though true blood flow can actually be obtained using MRI and other modalities. Ultrasound is regularly used to measure blood flow and is, under certain conditions, able to provide quantitative volumetric blood flow in milliliters per minute. Unfortunately, most times the resulting flow data is not valid due to unmet assumptions (such as flow profile and angle correction). Color flow, acquired in three dimensions, has been shown to yield quantitative blood flow without any assumptions (3DVF). Here we are testing whether color flow can perform during physiological conditions common to severe injury. Specifically, we are simulating severe traumatic brain injury (epidural hematoma) as well as hemorrhagic shock with 50% blood loss. Blood flow was measured in the carotid artery of a cohort of 7 Yorkshire mix pigs (40–60 kg) using 3DVF (4D16L, LOGIQ 9, GE HealthCare, Milwaukee, WI, USA) and compared to an invasive flow meter (TS420, Transonic Systems Inc., Ithaca, NY, USA). Six distinct physiological conditions were achieved: baseline, hematoma, baseline 2, hemorrhagic shock, hemorrhagic shock plus hematoma, and post-hemorrhage resuscitation. Mean cerebral oxygen extraction ratio varied from 40.6% ± 13.0% of baseline to a peak of 68.4% ± 15.6% during hemorrhagic shock. On average 3DVF estimated blood flow with a bias of -9.6% (-14.3% root mean squared error) relative to the invasive flow meter. No significant flow estimation error was detected during phases of flow reversal, that was seen in the carotid artery during traumatic conditions. The invasive flow meter showed a median error of -11.5% to 39.7%. Results suggest that absolute volumetric carotid blood flow to the brain can be obtained and potentially become a more specific biomarker related to cerebral hemodynamics than current surrogate markers. [ABSTRACT FROM AUTHOR]

Orthognathic surgery has the potential to compromise the vitality of the teeth. This paper aims to assess changes in pulp blood flow (PBF) and pulp sensibility (PS) of the anterior dentition following orthognathic surgery and to assess the influence of the proximity of the surgical osteotomy on the PBF and/or PS. Twenty-six patients undergoing orthognathic surgery (Le Fort I or bilateral sagittal split osteotomy [BSSO]) were compared to sixteen control patients treated by fixed appliances only using Laser Doppler flowmeter (LDF) and thermal testing (CO2 snow). Surgery patients were tested at T1 (presurgery), T2 (4-5 weeks postsurgery), T3 (3 months postsurgery), and T4 (6 months postsurgery). Control patients were tested at T1 (pretreatment), T2 (6 months posttreatment), T3 (12 months posttreatment), and T4 (18 months posttreatment). Differences between the maxilla and mandible were assessed. No differences in PBF or PS were recorded in the control group. In the surgery group, both jaws followed the same pattern after surgery, an initial decrease at T2 followed by a gradual recovery to pretreatment PBF levels with no significant difference between T1 versus T4 in both jaws. No difference in PBF was observed between the maxilla and mandible at any testing time interval. PBF and PS of the anterior dentition was severely affected immediately postsurgery, followed by a gradual increase to full recovery. This pattern of recovery was exhibited in both jaws. A negative sensibility response or discoloration should not be seen as an indication of irreversible ischemic pulp changes. Monitoring for at least 6 months or using LDF as a confirmatory test is required before any irreversible endodontic treatment is to be considered. [ABSTRACT FROM AUTHOR]

Reduced effect of antiplatelet therapy has been reported in patients with ST-segment elevation myocardial infarction (STEMI). Multiple factors may concur to explain this, including increased amount of highly reactive immature platelets. To investigate the association between immature platelets and reactivity determined with multicolour flow cytometry using the SYTO-13 dye in STEMI patients. We conducted an observational study of 59 patients with acute STEMI. Blood samples were obtained within 24 h after admission and after loading doses of dual antiplatelet therapy. For comparison, samples were obtained from 50 healthy individuals. Immature platelets and platelet reactivity were investigated using multicolour flow cytometry including the SYTO-13 dye that binds to platelet RNA and thus provides a method for subdividing platelets into immature and mature platelets. Additionally, we assessed platelet aggregation, serum-thromboxane B 2 levels and standard immature platelet markers. Immature platelets were more reactive than mature platelets in both STEMI patients and healthy individuals (p -values < 0.05). STEMI patients had lower platelet aggregation and thromboxane B 2 levels than healthy individuals. We found a positive association between automatically determined immature platelet markers and CD63 expression on activated platelets (Spearman's rho: 0.27 to 0.58, p -values < 0.05). Our study shows that immature platelets identified with a multicolour flow cytometric method using the SYTO-13 dye are more reactive than mature platelets in patients with acute STEMI and in healthy individuals. The presence of immature platelets may be important for the overall platelet reactivity, which may have implications for the effect of antiplatelet therapy. We included 59 patients diagnosed with acute ST-segment elevation myocardial infarction (STEMI) and 50 healthy individuals. Following blood sampling, we utilized whole blood multicolor flow cytometry, incorporating the SYTO-13 dye, which binds to platelet RNA. This approach allows us to subdivide platelets into immature and mature, enabling a comprehensive assessment of platelet reactivity across distinct platelet subpopulations. [Display omitted] • Reduced effect of antiplatelet therapy is observed in acute STEMI patients. • Immature platelets may influence platelet reactivity and the effect of antiplatelet therapy. • Results provided by a multicolour flow cytometric method using the SYTO-13 dye. • Immature platelets were more reactive than mature platelets in STEMI patients. • This study emphasizes the importance of immature platelets for the overall platelet reactivity. [ABSTRACT FROM AUTHOR]

Arteriovenous malformation is a disease of the vascular system that occurs mainly in the cerebral arteries and spine. Numerical simulation as a powerful method is used to investigate the Cerebral Arteriovenous Malformation hemodynamic after occlusion of the abnormality step by step by embolization. The computed tomography (CT) Angiographic imaging data of 2 patients are used and a geometric model is extracted by the Mimics software. Numerical simulation of blood flow is performed in both Newtonian and non-Newtonian models. The Navier–Stokes and continuity governing equations are solved by a finite element method using the COMSOL Multiphysics software (the commercial computational fluid dynamics (CFD) simulation software). To validate the numerical results, the real data on blood flow rate in the feeding artery and draining veins are used, as well as angiographic images at different times. Regarding the comparison of pressure contours for different occlusions of 0, 30, 50, and 90%, by increasing the amount of occlusion in the nidus, there is an increase in the blood pressure. Regarding the comparison of the blood flow velocity in the feeding artery, draining veins, and inside the AVM nidus for Newtonian and non-Newtonian models, there is a significant difference between these 2 simulations in vessels with smaller dimensions (such as vessels inside the nidus). By increasing the amount of nidus occlusion, the blood pressure is increased, so the blood supply process is better. According to a significant difference between the Newtonian and non-Newtonian simulations in vessels with smaller dimensions (such as vessels inside the nidus), therefore, non-Newtonian simulation should be done for different occlusions of 30, 50, and 90%. [ABSTRACT FROM AUTHOR]

To investigate the feasibility of obtaining black-blood imaging with a large FOV from the neck to the aortic arch at 3 T using a newly modified Relaxation-Enhanced Angiography without Contrast and Triggering for Black-Blood Imaging (REACT-BB). REACT-BB provides black-blood images by adjusting the inversion time (TI) in REACT to the null point of blood. The optimal TI for REACT-BB was investigated in 10 healthy volunteers with TI varied from 200 ms to 1400 ms. Contrast ratios were calculated between muscle and three branch arteries of the aortic arch. Additionally, a comparison between REACT-BB and MPRAGE involved evaluating the depiction of high-intensity plaques in 222 patients with stroke or transient ischemic attack. Measurements included plaque-to-muscle signal intensity ratios (PMR), plaque volumes, and carotid artery stenosis rates in 60 patients with high-intensity plaques in carotid arteries. REACT-BB with TI = 850 ms produced the black-blood image with the best contrast between blood and background tissues. REACT-BB outperformed MPRAGE in depicting high-intensity plaques in the aortic arch (55.4% vs 45.5%) and exhibited superior overall image quality in visual assessment (3.31 ± 0.70 vs 2.89 ± 0.73; p < 0.05). Although the PMR of REACT-BB was significantly lower than MPRAGE (2.227 ± 0.601 vs 2.285 ± 0.662; P < 0.05), a strong positive correlation existed between REACT-BB and MPRAGE (ρ = 0.935; P < 0.05), and all high-intensity plaques that MPRAGE detected were clearly detected by REACT-BB. REACT-BB provides black-blood images with uniformly suppressed fat and blood signals over a large FOV from the neck to the aortic arch with comparable or better high-signal plaque depiction than MPRAGE. • New flow-independent black blood imaging without respiratory triggering. • Robust and uniform blood and fat suppression over a large field of view. • Blood signal suppression unaffected by blood flow velocity or vascular anatomy. • Superior to conventional method in depicting vulnerable plaque in aortic arch. • Useful for detecting vulnerable plaques from neck to aortic arch in a short time. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the thermoregulatory responses between self-paced and fixed-intensity exercise matched for average workload, in different thermal profiles matched for vapour pressure. Thirteen moderate to highly trained cyclists [maximal oxygen uptake: 59 (2.5) ml/kg/min; peak power output: 392.7 (14.1) W] were recruited, where they underwent two 30 min self-selected pace trials and two 30 min fixed-intensity trials in 35 ̊C [34.9 (0.2)̊C; relative humidity: 50.1 (1.1)%; absolute humidity: 2.80 (0.1) kPa] and 29 ̊C [29.2 (0.2)̊C; 69.4 (0.9)%; 2.81 (0.05) kPa] with the same vapour pressure. The exercise intensity of the fixed-intensity trial was based on the average power output of the self-paced trial. Despite cutaneous blood flow at the forearm region showing counter intuitive results [35 ̊C: self-paced vs. fixed-intensity, 279.1 (28.4) vs. 227.1 (19.1) AU, P =.042; 29 ̊C: 301.3 (25.8) vs. 378 (39.1) AU, P =.03], all others variables were not different between self-paced and fixed-intensity or different thermal profiles, such as rectal temperature [35 ̊C: self-paced vs. fixed-intensity, 38.0 (0.1) vs. 37.9 (0.1) ̊C; 29 ̊C: 37.9 (0.1) vs. 38.0 (0.1) ̊C, all P >.2], skin temperature [35 ̊C: self-paced vs. fixed-intensity, 36.3 (0.1) vs. 36.2 (0.1) ̊C; 29 ̊C: 34.5 (0.2) vs. 34.4 (0.2) ̊C, all P >.4]. We conclude that self-paced exercise does not reduce thermoregulatory strain in mild and moderate heat, when average workload is matched. [ABSTRACT FROM AUTHOR]

Neurovascular coupling (NVC) represents the increase in regional blood flow associated with neural activity. The aim here was to describe a new approach to non-invasive measurement of NVC by spectral analysis of the cerebral blood flow velocity (CBFV) with transcranial Doppler. In a sample of 20 healthy participants, we monitored systolic CBFV in the left posterior cerebral artery (PCA) during off (eyes closed) and on (flickering checkerboard) periods. The contralateral middle cerebral artery was simultaneously monitored as a control. Each participant was submitted to three experiments, each having five cycles, with increasing duration of the cycles, from 10 s (0.1 Hz) to 20 s (0.05 Hz) and lastly 40 s (0.025 Hz), half the time for on and for off periods, constituting a total of 6 min. The successive cycles were expected to cause oscillation in CBFV in a sinusoidal pattern that could be characterized by spectral analysis. We also measured the classic CBFV overshoot as the relative increase in percentage of systolic CBFV from baseline. The relationship and agreement between the two methods were analyzed by linear regression and Bland–Altman plots. In every participant, a clear peak of amplitude in the PCA CBFV spectrum was discernible at 0.1, 0.05 and 0.025 Hz of visual stimulation. On average, this amplitude was 7.1 ± 2.3%, 10.9 ± 3.5% and 17.3 ± 6.5%, respectively. This response contrasted significantly with an absent peak in middle cerebral artery monitoring (p < 0.0001). The spectral amplitude and classic overshoot were highly correlated and linearly related (p < 0.0001). NVC can be quantified by the spectral amplitude of PCA CBFV at slower and higher frequencies of visual stimulation. This method represents an alternative to classic overshoot without the need for stimulus marking or synchronization. [ABSTRACT FROM AUTHOR]

Acute pulmonary embolism (PE) is a serious condition that needs quick and effective treatment. Anticoagulation therapy is the usual care for most PE patients but may not work well for higher-risk ones. Thrombolysis breaks the clot and improves blood flow. It can be given systemically or locally. Ultrasound-assisted catheter-directed thrombolysis (USAT) is a new technique that boosts clot-busting drugs. This network meta-analysis compares death, bleeding, and benefits of four treatments in acute submassive PE. We comprehensively searched relevant databases up to July 2023 for RCTs. The outcomes encompassed all-cause mortality, major and minor bleeding, PE recurrence, and hospital stay duration. Bayesian network meta-analysis computed odds ratios (OR) and 95 % CI estimates. In this network meta-analysis of 23 RCTs involving 2521 PE patients, we found that SCDT had the most favorable performance for mortality, as it had the lowest odds ratio (OR) among the four interventions (OR 5.41e−42; 95 % CI, 5.68e−97, 1.37e−07). USAT had the worst performance for major bleeding, as it had the highest OR among the four interventions (OR 4.73e+04; 95 % CI, 1.65, 9.16e+13). SCDT also had the best performance for minor bleeding, as it had the lowest OR among the four interventions (OR 5.68e−11; 95 % CI, 4.97e−25, 0.386). Our meta-analysis suggests that SCDT is the most effective treatment intervention in improving the risks of All-cause mortality and bleeding. Thrombolytic therapy helps in improving endpoints including the risk of PE recurrence and the duration of hospital stay. [Display omitted] • We compared different types of thrombolysis for acute submassive pulmonary embolism (PE). • This is a network meta-analysis of 23 randomized controlled trials with 2521 PE patients. • Standard catheter-directed thrombolysis (SCDT) was associated with the lowest mortality and bleeding risks. • Thrombolytic therapy reduces PE recurrence and hospital stay duration. [ABSTRACT FROM AUTHOR]

The homeostatic and excretory functions of the kidney are dependent on its perfusion, totalling 20–25% of cardiac output, and the process of glomerular ultrafiltration. Renal blood flow (RBF) is directly proportional to the trans-renal gradient which is autoregulated across a mean arterial pressure of 50–150 mmHg in a normotensive person. Selective molecular filtration in the glomerulus is achieved by the glomerular filtration barrier and is related to the size, shape, and electrical charge of molecules. The process of ultrafiltration is determined by the balance between hydrostatic and colloid osmotic pressures in the glomerular capillary and Bowman's space, and is affected by renal plasma flow, altered surface area and changes in afferent and efferent renal arteriole vascular resistance. The phenomenon of renal plasma flow autoregulation minimizes changes in the volume of ultrafiltration through myogenic and tubuloglomerular feedback mechanisms. Glomerular filtration rate can be measured using exogenous inulin, or estimated (eGFR) from creatinine clearance, several equations can be used to calculate eGFR but their limitations in estimating the true excretory function of the kidney need to be taken into consideration. [ABSTRACT FROM AUTHOR]

The emerging high-frame-rate vector flow imaging provides a new way of hemodynamic evaluation for complex blood flow. This study was aimed at exploring quantitatively the characteristics of complex flow with turbulence (Tur) index and analyzing flow patterns in atherosclerotic internal carotid artery stenosis (ICAS) using high-frame-rate vector flow imaging. This study prospectively included 60 patients with ICAS. Tur values in different segments of stenosis and cardiac phases were compared. Spearman correlation analysis was performed between clinical plaque characteristics with turbulence grading by ln(Tur). Three complex flow patterns were qualitatively drawn on vector flow mode, and the rates of detection of flow patterns in different stenosis groups and ulceration groups were compared. Highly disordered blood flow was observed in the stenotic (Tur [M, QR] = 12.5%, 21.5%) and distal segment (15.4%, 27.2%), particularly during systole (21.0%, 30.7%, 33.3%, 38.7%, p < 0.05). Spearman correlation analysis revealed that stenosis rate was correlated with turbulence grading in the stenotic (ρ = 0.65, p < 0.05) and distal segment (ρ = 0.79, p < 0.05), and ulcer formation was correlated with turbulence grading in the stenotic segment (ρ = 0.58, p < 0.05). The overall rate of detection of three flow patterns was higher in the severe stenosis group (22/22) versus the mild to moderate stenosis group (21/38) (p < 0.001) and in the ulcer group (21/23) versus the non-ulcer group (23/37) (p < 0.001). High-frame-rate vector flow imaging was helpful in assessing the severity and characteristics of flow turbulence. Lumen geometric factors could affect flow turbulence and blood flow patterns around the plaque. This would provide important hemodynamic information for the detection of high-risk plaque. [ABSTRACT FROM AUTHOR]

Recent clinical data indicate a different performance of biodegradable polymer (BP)-drug eluting stent (DES) compared to durable polymer (DP)-DES. Whether this can be explained by a beneficial impact of BP-DES stent design on the local hemodynamic forces distribution remains unclear. To compare endothelial shear stress (ESS) distribution after implantation of ultrathin (us) BP-DES and DP-DES and examine the association between ESS and neointimal thickness (NIT) distribution in the two devices at 9 months follow up. We retrospectively identified patients from the BIOFLOW II trial that had undergone OCT imaging. OCT data were utilized to reconstruct the surface of the stented segment at baseline and 9 months follow-up, simulate blood flow, and measure ESS and NIT in the stented segment. The patients were divided into 3 groups depending on whether DP-DES (N = 8, n = 56,160 sectors), BP-DES with a stent diameter of >3 mm (strut thickness of 80 μm, N = 6, n = 36,504 sectors), or BP-DES with a stent diameter of ≤3 mm (strut thickness of 60 μm, N = 8, n = 50,040 sectors) were used for treatment. The ESS, and NIT distribution and the association of these two variables were estimated and compared among the 3 groups. In the DP-DES group mean NIT was 0.18 ± 0.17 mm and ESS 1.68 ± 1.66 Pa; for the BP-DES ≤3 mm group the NIT was 0.17 ± 0.11 mm and ESS 1.49 ± 1.24 Pa and for the BP-DES >3 mm group 0.20 ± 0.23 mm and 1.42 ± 1.24 Pa respectively (p < 0.001 for both NIT and ESS comparisons across groups). A negative correlation between NIT and baseline ESS was found, the correlation coefficient for all the stented segments was −0.33, p < 0.001. In this OCT sub-study of the BIOFLOW II trial, the NIT was statistically different between groups of patients treated with BP-DES and DP-DES. In addition, regions of low ESS were associated with increased NIT in all studied devices. • This is the first study that evaluates, compares, and relates neointimal thickness (NIT) with endothelial shear stress (ESS) in biodegradable polymer drug-eluting stents versus traditional 2nd generation durable polymer drug-eluting stents. • Neo-intimal thickness in the stented segment was different in biodegradable polymer drug-eluting stents versus 2nd generation durable polymer drug-eluting stents. • This difference was statistically significant, but marginal and may not be clinically relevant. • A negative correlation was seen between endothelial shear stress and neointimal thickness as regions of low ESS were associated with increased NIT. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare physiological responses to myofascial release (MFR) and passive limb movement (PLM). Nineteen (23 ± 2.6yrs) adults (10 men and 9 women) completed two experiments on separate days: MFR and PLM. Participation included collecting ultrasound images, blood pressure, and heart rate (HR) as well as performing a vascular occlusion test (VOT). The VOT assessed muscle tissue oxygenation (StO 2) with near-infrared spectroscopy. Experiments consisted of moving the upper limb to release subtle barriers of resistance in the muscle/fascia (MFR) and passive, assisted range of motion (PLM). There was a significantly (p = 0.012) greater decrease in HR following MFR (−7.3 ± 5.2 BPM) than PLM (−1.3 ± 0.9 BPM). There was an equivalent change in brachial blood flow (−17.3 ± 23.0 vs. −11.9 ± 14.9 mL min−1; p = 0.37) and vascular conductance (−19.3 ± 31.1 vs. −12.4 ± 15.3 mL min−1 mmHg−1; p = 0.38). Microvascular responses differed between the experiments such that MFR exhibited greater area under the curve (AUC, 1503 ± 499.1%∙s−1 vs. 1203 ± 411.1%∙s−1; p = 0.021) and time to maximum StO 2 (40.0 ± 8.4s vs. 35.8 ± 7.3s; p = 0.009). As evidenced by HR, MFR induced greater parasympathetic activity than PLM. The greater AUC and time to StO 2max following MFR suggested a spillover effect to induce prolonged hyper-saturation. These results may be of interest to those investigating possible MFR-related rehabilitative benefits. • Heart rate significantly decreased following myofascial release. • Myofascial release provoked downstream prolonged hyper-saturation. • Time to reach peak oxygenation was greater after myofascial release than control. [ABSTRACT FROM AUTHOR]

There is a lack of data regarding the baseline hemodynamic blood flow parameters of the wrist and digits. Therefore, we aimed to quantify the digital and radial artery blood flow parameters using ultrasound and assess the influence of patient characteristics on hemodynamics. We analyzed ultrasonographic data from 25 patients (50 hands) between October 2019 and December 2021. Variables of interest included dimensions of the radial artery and index finger (IF) ulnar and radial digital arteries at the palmodigital crease and their corresponding flow parameters. We compared variables among men and women and patients with and without diabetes using Wilcoxon Rank Sum test. Our cohort consisted of 18 women (36 hands) and three participants with diabetes (six hands). The mean diameter of the IF radial digital artery was 7 mm, and that of the ulnar digital artery was 10 mm. The average peak systolic velocity for the radial digital artery was 21.31 cm/sec, and for the ulnar digital artery, it was 30.03 cm/sec. Comparing men and women, the only significant difference found was in the time-averaged mean velocity for the ulnar digital artery (men:5.66 cm/sec vs. women:9.68 cm/sec, P = 0.02) and volume of flow for the ulnar digital artery (men:10.87cc/min vs. women:18.58cc/min, P = 0.03). We found no differences in blood flow parameters comparing participants with and without diabetes. These data provide a baseline measurement of digital flow hemodynamics that can be used in future studies to model vascular flow after replantation. [ABSTRACT FROM AUTHOR]

The effects of helical flow in a blood vessel are investigated in a dynamic flow generator using surface acoustic wave (SAW) in the microfluidic device. The SAW, generated by an interdigital transducer (IDT), induces acoustic streaming, resulting in a stable and consistent helical flow pattern in microscale channels. This approach allows rapid development of helical flow within the channel without directly contacting the medium. The precise design of the window enables the creation of distinct unidirectional vortices, which can be controlled by adjusting the amplitude of the SAW. Within this device, optimal operational parameters of the dynamic flow generator to preserve the integrity of endothelial cells are found, and in such settings, the actin filaments within the cells are aligned to the desired state. Our findings reveal that intracellular Ca2+ concentrations vary in response to flow conditions. Specifically, comparable maximum intensity and graphical patterns were observed between low-flow rate helical flow and high-flow rate Hagen-Poiseuille flow. These suggest that the cells respond to the helical flow through mechanosensitive ion channels. Finally, adherence of monocytes is effectively reduced under helical flow conditions in an inflammatory environment, highlighting the atheroprotective role of helical flow. Helical flow in blood vessels is well known to prevent atherosclerosis. However, despite efforts to replicate helical flow in microscale channels, there is still a lack of in vitro models which can generate helical flow for analyzing its effects on the vascular system. In this study, we developed a method for generating steady and constant helical flow in microfluidic channel using acoustofluidic techniques. By utilizing this dynamic flow generator, we were able to observe the atheroprotective aspects of helical flow in vitro, including the enhancement of calcium ion flux and reduction of monocyte adhesion. This study paves the way for an in vitro model of dynamic cell culture and offers advanced investigation into helical flow in our circulatory system. [Display omitted] [ABSTRACT FROM AUTHOR]

Moyamoya disease is a bilateral steno-occlusive disease involving the cerebral vasculature. While some patients are affected by procedure-related ipsilateral ischemia, ischemic complications contralateral to the revascularization are rarely observed. We retrospectively investigated 135 hemispheres (103 patients) that underwent revascularization in our institution between April 2006 and September 2022. Revascularization surgery comprised single superficial temporal artery-middle cerebral artery anastomosis and encephalo-myo-synangiosis. Certain patients aged under 10 years underwent indirect revascularization. Bilateral revascularization was performed with an interval of >3 months. Medical records and neuroimages were reviewed, and patients with contralateral ischemic complications were identified. Some cases underwent genetic analysis. The mean age was 34.5 (range: 5–71) years, and 95 cases (70.4%) were in women. Of the 102 cases examined for the RNF213 c.14429 G > A (p.Arg4810Lys) variant, 33 (32.4%) and 69 (67.6%) showed the GG and GA genotype, respectively. Three cases (2.2%, all female, age range 44–71 years) were complicated with contralateral infarction. The infarcted area distributions of the 2 cases with RNF 213 c.14429 G > A variant were patchy and peripheral. The other case showed on magnetic resonance imaging (MRI) angiography total occlusion of the internal carotid artery where patency had been confirmed preoperatively. Contralateral ischemia after revascularization occurred in 2.2% of cases. We classified them into peripheral and central types: peripheral type, an infarction owing to hemodynamic insufficiency or intracranial blood flow redistribution; central type, total occlusion of the contralateral internal carotid artery. Intensive preoperative management can minimize the risk of peripheral types, and neurosurgeons should beware of severe central types. [ABSTRACT FROM AUTHOR]

Cardiac allograft vasculopathy (CAV) limits long-term survival after heart transplantation (HT). This study evaluates the relationship between clinically significant cytomegalovirus infection (CS-CMVi) and CAV using cardiac positron emission tomography (PET). We retrospectively evaluated HT patients from 2005 to 2019 who underwent cardiac PET for CAV evaluation. Multivariable linear and logistic regression models were used to evaluate the association between CS-CMVi and myocardial flow reserve (MFR). Kaplan-Meier and Cox regression analyses were used to assess the relationship between CS-CMV, MFR, and clinical outcomes. Thirty-two (31.1%) of 103 HT patients developed CS-CMVi at a median 9 months after HT. Patients with CS-CMVi had a significantly lower MFR at year 1 and 3, driven by reduction in stress myocardial blood flow. Patients with CS-CMVi had a faster rate of decline in MFR compared to those without infection (−0.10 vs −0.06 per year, p < 0.001). CS-CMVi was an independent predictor of abnormal MFR (<2.0) (odds ratio: 3.8, 95% confidence intervals (CI): 1.4-10.7, p = 0.001) and a lower MFR (β = −0.39, 95% CI: −0.63 to −0.16, p = 0.001) at year 3. In adjusted survival analyses, both abnormal MFR (log-rank p < 0.001; hazard ratio [HR]: 5.7, 95% CI: 4.2-7.2) and CS-CMVi (log-rank p = 0.028; HR: 3.3, 95% CI: 1.8-4.8) were significant predictors of the primary outcome of all-cause mortality, retransplantation, heart failure hospitalization, and acute coronary syndrome. CS-CMVi is an independent predictor of reduced MFR following HT. These findings suggest that CMV infection is an important risk factor in the development and progression of CAV. [ABSTRACT FROM AUTHOR]

Post-operative brain injury in neonates may result from disturbed cerebral perfusion, but accurate peri-operative monitoring is lacking. High-frame-rate (HFR) cerebral ultrasound could visualize and quantify flow in all detectable vessels using spectral Doppler; however, automated quantification in small vessels is challenging because of low signal amplitude. We have developed an automatic envelope detection algorithm for HFR pulsed wave spectral Doppler signals, enabling neonatal brain quantitative parameter maps during and after surgery. HFR ultrasound data from high-risk neonatal surgeries were recorded with a custom HFR mode (frame rate = 1000 Hz) on a Zonare ZS3 system. A pulsed wave Doppler spectrogram was calculated for each pixel containing blood flow in the image, and spectral peak velocity was tracked using a max-likelihood estimation algorithm of signal and noise regions in the spectrogram, where the most likely cross-over point marks the blood flow velocity. The resulting peak systolic velocity (PSV), end-diastolic velocity (EDV) and resistivity index (RI) were compared with other detection schemes, manual tracking and RIs from regular pulsed wave Doppler measurements in 10 neonates. Envelope detection was successful in both high- and low-quality arterial and venous flow spectrograms. Our technique had the lowest root mean square error for EDV, PSV and RI (0.46 cm/s, 0.53 cm/s and 0.15, respectively) when compared with manual tracking. There was good agreement between the clinical pulsed wave Doppler RI and HFR measurement with a mean difference of 0.07. The max-likelihood algorithm is a promising approach to accurate, automated cerebral blood flow monitoring with HFR imaging in neonates. [ABSTRACT FROM AUTHOR]

Childhood arterial ischaemic stroke (AIS) is a significant health concern with increasing incidence. This review aims to provide an overview of the current understanding of childhood AIS. The incidence of childhood AIS is on the rise especially in developing countries, likely due to improved awareness and diagnostic capabilities. Aetiology of childhood AIS is multifactorial, with both modifiable risk factors and genetic predisposition playing important roles. Identifying and addressing these risk factors, such as infection, sickle cell disease, and congenital heart defects, is essential in prevention and management. Identifying underlying conditions through genetic testing is important for appropriate management and long-term prognosis. Clinically, distinguishing stroke from stroke mimics can be challenging. Awareness of important stroke mimics, including migraines, seizures, and metabolic disorders, is crucial to avoid misdiagnosis and ensure appropriate treatment. The diagnostic approach to childhood AIS involves a comprehensive "chain of care," including initial assessment, neuroimaging, and laboratory investigations. National guidelines play a pivotal role in standardizing and streamlining the diagnostic process, ensuring prompt and accurate management. Early intervention is critical in the management of childhood AIS. Due to the critical time window, the question if mechanical thrombectomy is feasible and beneficial should be addressed as fast as possible. Early initiation of antiplatelet or anticoagulation therapy and, in select cases, thrombolysis can help restore blood flow and minimize long-term neurological damage. Additionally, rehabilitation should start as soon as possible to optimize recovery and improve functional outcomes. In conclusion, childhood AIS is a growing concern. Understanding the increasing incidence, age distribution, risk factors, clinical presentation, diagnostic approach, and management strategies is crucial for optimized management of these patients. [ABSTRACT FROM AUTHOR]

Obesity is the most common health issue in women of reproductive age, which profoundly affects maternal-fetal health. Despite progress in understanding key inflammatory and metabolic changes, the pathogenesis of the cardiovascular phenotype of obese pregnant women remains to be fully understood. This study aimed at: (i) evaluating the changes of the renin-angiotensin system (RAS) throughout pregnancy in obese vs normal weight (control) women, and (ii) evaluating the presence of any associations between maternal hemodynamic status and RAS changes. Thirty-eight normal weight and nineteen obese pregnant women were included. Clinical assessment, blood samples and maternal hemodynamic evaluation were performed at 12, 20, 30, and 36 weeks, while ultrasound assessment was scheduled at 20, 30, and 36 weeks of gestation. Measurements of sFlt-1, PlGF, Angiotensinogen, Renin, AngII, Ang1-7, ACE and ACE2 were performed by ELISA. Our data show that normotensive obese women had lower placental blood supply, as assessed by UV-Q and UV-Q/EFW, as compared to controls, and significantly higher levels of AngII and AngII/Ang1-7 ratio, which were inversely related to placental blood supply. Our study shows for the first time that normotensive obese women exhibited a significant progressive increase of AngII and AngII/Ang1-7 throughout pregnancy, which were inversely related to placental blood supply as assessed by UV-Q and UV-Q/EFW. Our data shed light on the early changes in pregnant obese women and suggest that RAS dysregulation is a prerequisite rather than a consequence of hypertensive disorders of pregnancy and other maternal neonatal complications. • Angiotensin II significantly increased in normotensive obese pregnant women and this was related to placental blood supply. • Placental blood supply was reduced in normotensive obese pregnant women at 30 weeks of gestation. • Our data suggest that RAS dysregulation may be a prerequisite of hypertensive disorders of pregnancy in obesity. [ABSTRACT FROM AUTHOR]

To describe and present the results of the use of urogenital mobilization extended by two flaps from the redundant distal part of the urethra in the correction of a severe form of distal vaginal agenesis. During the past 4 years (from December 2018 to March 2023), we have performed 2 vaginoplasties using the described procedure. The age of the patients at surgery was 13 years. Two girls presented with primary amenorrhea associated with cyclic pelvic pain evolving over several months. Clinical examination revealed a blind vagina and an anterior pelvic mass. Ultrasound and magnetic resonance imaging showed a severe form of distal vaginal agenesis. One patient had a 47,XX+mark karyotype and right vesicoureteral reflux. Two patients underwent urogenital mobilization, guided by a tube introduced into the upper part of the vagina through an abdominal approach, and the use of two flaps from the redundant distal part of the urethra to extend the neovagina to the perineum. The esthetic results were very satisfactory with the disappearance of pelvic pain, and the restoration of a regular flow of menstrual blood without pain. Urinary continence was preserved in two patients. This is the first report of the use of urogenital mobilization extended two flaps from the redundant distal part of the urethra in the correction of a severe form of distal vaginal agenesis. This procedure yielded a very satisfactory esthetic and functional results. [ABSTRACT FROM AUTHOR]

To analyse the performance of arterial spin labelling (ASL) in predicting surgical bleeding in a paediatric cohort of optic pathway glioma (OPG). Preoperative ASL data were obtained for 51 OPG in 40 patients, aged from 9 months to 16 years. The relative cerebral blood flow (rCBF) in the tumour areas with the highest CBF (maximum rCBF) was measured and then correlated with qualitative local bleeding (graded no, moderate, and major by the neurosurgeon) and quantitative global surgical bleeding (assessed in millilitres using haematocrit data). Intratumoural maximum rCBF was significantly higher when qualitative local bleeding was high (median value in the no, moderate, and major bleeding groups equal to 0.81, 1.39 and 4.22, respectively, p= 0.004), but there was no difference in global quantitative bleeding (p= 0.7 for the total blood loss). The maximum tumour rCBF cut-off value of 1.1 yielded a sensitivity of 73%, a specificity of 78%, and an accuracy of 76% (39/51 tumours) in detecting haemorrhagic OPG. Choosing a maximum tumour rCBF cut-off value > 1.7 improved the specificity in diagnosing tumours with high bleeding risk with a specificity of 94%, a sensitivity of 53%, and an accuracy of 82% (42/51 tumours). ASL tumoural rCBF is a useful and simple diagnostic tool to help predict high intraoperative tumoural bleeding risk in paediatric OPG. • Tumor cerebral blood flow helps to predict qualitative surgical bleeding. • Relative tumor blood flow greater than 1.1 is associated with hemorrhagic glioma. • Larger resected area is associated with higher quantitative hemorrhage. [ABSTRACT FROM AUTHOR]

Arterial Spin Labeling (ASL) allows for the non-invasive visualization of brain perfusion to detect abnormalities. In unilateral carotid artery stenosis, one hemisphere is less supplied with blood which results in a lower cerebral blood flow (CBF) compared to the healthy side. ASL can be performed time-resolved using multiple post labeling delay (PLD) times after labeling or static with a single delay, the latter allowing for a faster and more robust acquisition while bearing the risk of a falsely set delay resulting in unusable images. The purpose of this study is to compare the performance of multi-PLD and single-PLD ASL in patients with unilateral carotid artery stenosis both as means of diagnosis and therapeutic follow-up examination. ASL perfusion data of 17 patients with known unilateral carotid artery stenosis was used to compare the diagnostic performance of the multi-PLD and single-PLD approach. Comparisons were made based on the CBF values and the added benefit of arrival time maps showing slower blood flow in multi-PLD ASL which might be overlooked in the individual delay images both before and after therapy. Both the multi-PLD and the single-PLD data could identify the side of the stenosis with hemispheric differences in each approach (p < 0.001) and depict the normalization of CBF after therapy (p > 0.05). There were no differences between the individual methods (p > 0.05). In this work, we could show that multi-PLD ASL in patients with unilateral carotid artery stenosis is beneficial as it provides both CBF and arrival time maps, however when only a single-PLD acquisition is available, this appears sufficient in a clinical setting to investigate the presence of a unilateral stenosis. [ABSTRACT FROM AUTHOR]

Thrombotic disease may be an underdiagnosed condition of prolonged exposure to microgravity and yet the underlying factors remain poorly defined. Recently, an internal jugular vein thrombosis was diagnosed in a low-risk female astronaut after an approximately 7-week space mission. Six of the additional 10 crew members demonstrated jugular venous flow risk factors, such as suspicious stagnation or retroversion. Fortunately, all were asymptomatic. Observations in space as well as clinical and in vitro microgravity studies on Earth, where experiments are designed to recapitulate the conditions of space, suggest effects on blood flow stasis, coagulation, and vascular function. In this article, the related literature on thrombotic disease in space is reviewed, with consideration of these elements of Virchow's triad. • Asymptomatic internal jugular vein thrombosis (IJV) was detected in an astronaut. • Exposure to microgravity may cause unforeseen risk during long-term spaceflight. • Studies on thrombosis risk in space and analogous models on Earth are limited. • Microgravity affects the blood flow stasis, coagulation, and endothelial triad. • Here, the pathophysiological and biomolecular evidence are examined. [ABSTRACT FROM AUTHOR]

Nitrite (NO 2 −) interacts with hemoglobin (Hb) in various ways to regulate blood flow. During hypoxic vasodilation, nitrite is reduced by deoxyHb to yield nitric oxide (NO). While NO, a hydrophobic gas, could freely diffuse across the cell membrane, how the reactant nitrite anion could permeate through the red blood cell (RBC) membrane remains unclear. We hypothesized that Cl−/HCO 3 − anion exchanger-1 (AE1; band 3) abundantly embedded in the RBC membrane could transport NO 2 −, as HCO 3 − and NO 2 − exhibit similar hydrated radii. Here, we monitored NO/N 2 O 3 generated from NO 2 − inside human RBCs by DAF-FM fluorophore. NO 2 −, not NO 3 −, increased intraerythrocytic DAF-FM fluorescence. To test the involvement of AE1-mediated transport in intraerythrocytic NO/N 2 O 3 production from nitrite, we lowered Cl− or HCO 3 − in the RBC-incubating buffer by 20 % and indeed observed slower rise of the DAF-FM fluorescence. Anti-extracellular AE1, but not anti-intracellular AE1 antibodies, reduced the rates of NO formation from nitrite. The AE1 blocker DIDS similarly reduced the rates of NO/N 2 O 3 production from nitrite in a dose-dependent fashion, confirming that nitrite entered RBCs through AE1. Nitrite inside the RBCs reacted with both deoxyHb and oxyHb, as evidenced by 6.1 % decrease in deoxyHb, 14.7 % decrease in oxyHb, and 20.7 % increase in methemoglobin (metHb). Lowering Cl− in the milieu equally delayed metHb production from nitrite-oxyHb and nitrite-deoxyHb reactions. Thus, AE1-mediated NO 2 − transport facilitates NO 2 −-Hb reactions inside the red cells, supporting NOx metabolism in circulation. [Display omitted] [ABSTRACT FROM AUTHOR]

Physics-informed neural networks (PINN) architectures have been recently explored to accelerate hemodynamics simulations by leveraging mathematical models for blood flow and empirical data. In this paper, a variable separated physics-informed neural networks based on adaptive weighted loss functions (AW-vsPINN) is developed for blood flow model in arteries. In particular, sub-neural networks are proposed to separately predict the unknown scalar state variables by sharing the same input layer. The AW-vsPINN adaptively adjusts the weights of loss terms by the minmax algorithm, which will be updated synchronously along with the network parameters and can balance the contributions of different loss terms during training. The two-stage optimization is implemented to train the neural networks. Specifically, the Adam optimizer is iterated for initial steps with the learning rate generated by the inverse time decay scheduler, and then the L-BFGS optimizer continues to train until the loss converges. Numerical results illustrate that the AW-vsPINN can remarkably improve prediction accuracy and enhance the ability of generalization compared to the conventional PINN. The proposed AW-vsPINN framework has high potential in predicting the blood flow information in cardiovascular disease. [ABSTRACT FROM AUTHOR]

To evaluate the value of non-contrast micro-flow imaging (MFI) and high-definition micro-flow imaging (HD-MFI) in differentiating malignant and benign breast lesions. One hundred and thirty-three patients with 138 breast lesions (80 benign and 58 malignant lesions) were examined using colour Doppler flow imaging (CDFI), MFI, and HD-MFI before biopsy, with blood flow signals graded into four types (grade 0, 1, 2, and 3) and penetrating vessels evaluated. The micro-vascular patterns of MFI and HD-MFI were evaluated and classified into five patterns: avascular, line-like, tree-like, root hair-like, and crab claw-like pattern. The diagnostic efficiency of micro-vascular patterns was analysed. Moreover, ultrasound Breast Imaging Reporting and Data System (BI-RADS) 4A lesions were also re-assessed according to the micro-vascular patterns of MFI or HD-MFI. The capability of detecting blood flow and penetrating vessels from high to low was HD-MFI, MFI, and CDFI, respectively (p <0.05). Rich blood flow signals, penetrating vessels, and root hair-like or crab claw-like pattern were more likely in malignant breast lesions, while few blood flow signals, tree-like pattern were mostly in benign lesions (p <0.05). The diagnostic efficiency of HD-MFI and MFI were higher than CDFI (p >0.05). MFI could reduce unnecessary biopsy of 52 US BI-RADS 4A lesions but with two malignancies missed, while 56 ultrasound BI-RADS 4A lesions could be downgraded by HD-MFI with none malignancies missed. MFI and HD-MFI can detect more blood flow in breast lesions than CDFI, and could help distinguish benign and malignant breast lesions. HD-MFI could reduce the unnecessary biopsy of US BI-RADS 4A lesions without missed malignancy. • MFI and HD-MFI outperform CDFI in diagnosis of breast lesions. • Root hair-like and crab claw-like patterns are features of malignancies. • HD-MFI could downgrade US BI-RADS 4A lesions without malignancies missed. [ABSTRACT FROM AUTHOR]

The microcirculation describes the network of the smallest vessels in our cardiovascular system. On a microcirculatory level, oxygen delivery is determined by the flow of oxygen-carrying red blood cells in a given single capillary (capillary red blood cell flow) and the density of the capillary network in a given tissue volume (capillary vessel density). Handheld vital videomicroscopy enables visualisation of the capillary bed on the surface of organs and tissues but currently is only used for research. Measurements are generally possible on all organ surfaces but are most often performed in the sublingual area. In patients presenting for elective surgery, the sublingual microcirculation is usually intact and functional. Induction of general anaesthesia slightly decreases capillary red blood cell flow and increases capillary vessel density. During elective, even major, noncardiac surgery, the sublingual microcirculation is preserved and remains functional, presumably because elective noncardiac surgery is scheduled trauma and haemodynamic alterations are immediately treated by anaesthesiologists, usually restoring the macrocirculation before the microcirculation is substantially impaired. Additionally, surgery is regional trauma and thus likely causes regional, rather than systemic, impairment of the microcirculation. Whether or not the sublingual microcirculation is impaired after noncardiac surgery remains a subject of ongoing research. Similarly, it remains unclear if cardiac surgery, especially with cardiopulmonary bypass, impairs the sublingual microcirculation. The effects of therapeutic interventions specifically targeting the microcirculation remain to be elucidated and tested. Future research should focus on further improving microcirculation monitoring methods and investigating how regional microcirculation monitoring can inform clinical decision-making and treatment. [ABSTRACT FROM AUTHOR]

Spatiotemporal optical coherence tomography (STOC-T) is the novel modality for high-speed, crosstalk- and aberration-free volumetric imaging of biological tissue in vivo. STOC-T extends the Fourier-Domain holographic Optical Coherence Tomography by the spatial phase modulation that enables the reduction of spatial coherence of the tunable laser. By reducing the spatial coherence of the laser, we suppress coherent noise, and, consequently, improve the imaging depth. Furthermore, we remove geometrical aberrations computationally in postprocessing. We recently demonstrated high-speed, high-resolution STOC-T of human retinal imaging in vivo. Here, we show that the dataset produced by STOC-T can be processed differently to reveal blood flow in the human retina in vivo. To render the blood flow, we first pre-process STOC-T holographic data to access the approximated information about the Doppler-shifted optical field backscattered from the sample. Then, we analyze it using methods from the laser Doppler flowmetry, namely, by analyzing the Doppler broadening caused by moving light scatterers (red blood cells). However, contrary to conventional approaches, we use multiple illumination wavelengths. This enables us to render the structural volumetric and blood flow images from the same dataset concurrently. Our method, denoted as multiwavelength laser Doppler holography (MLDH), links laser Doppler flowmetry with multiwavelength holographic detection to enable noninvasive visualization and possible blood flow quantification at different human retina layers at high speeds and high transverse resolution in vivo. [ABSTRACT FROM AUTHOR]

A topic of current research is the development of a new approach to the diagnosis and treatment of severe brain injury taking into consideration its main pathophysiological mechanism—idiopathic intracranial hypertension syndrome. The goal of this study was to identify Doppler patterns of unfavorable craniocerebral injury conditions to form a consistent algorithm of treatment measures to reduce secondary brain damage in patients with severe craniocerebral trauma. Transcranial Doppler imaging is a prospective method, which allows quick and noninvasive assessment of the intracerebral blood flow dynamics right at the patient's bedside. Due to the operator-dependent nature of this method, clinical interpretation can often be contradictory. As a result, no clear criteria for therapy correction have yet been formulated based on this neuroimaging method. Analysis of the therapy performed allowed us to specify the options for the hyperosmolar solutions for the correction of idiopathic intracranial hypertension syndrome. No statistically significant difference in effectiveness was shown between mannitol and hypertonic saline solutions. [ABSTRACT FROM AUTHOR]